Flexner on Finishing: The Many Faces of Varnish

You are surely familiar with varnish. It is one of the oldest and most widely available wood finishes, and it is a very popular finish with amateur woodworkers. Varnish is easy to brush, and it provides excellent protection for wood surfaces and resistance to scratches, heat, solvents and chemicals.

You may not realize it, but varnish is packaged and sold under many different names, some with no indication that the product is simply varnish. If you count all the supposedly different finishing products that are actually just varnish, you probably have a shelf full. Here are the eight categories of varnish:
• alkyd varnish
• polyurethane
• spar varnish
• marine (boat) varnish
• wiping varnish (sold under many different
names)
• salad-bowl finish
• wood conditioner
• gel varnish